Art of producing multiple compartment bags



Jan. 16, 1962 w. A. SCHOEN ETAL ART OF PRODUCING MULTIPLE COMPARTMENT BAGS Filed Feb. 27, 1958 INVENTORS W.A.SCHOEN G.J.HERRICK ATTOR N EYS United States Patent 3,016,806 ART OF PRODUCING MULTIPLE COMPARTMENT BAGS Walter A. Schoen and George J. Herrick, Milwaukee, Wis., assignors to Milprint, Inc., Milwaukee, Wis., a corporation of Delaware Filed Feb. 27, 1958, Ser. No. 718,019 1 Claim. (Cl. 9335) The present invention relates generally to improvements in the art of producing multiple compartment bags; and it relates more specifically to an improved method of and apparatus for manufacturing bags from flexible sheet stock each having several segregated commodity receiving zones therein.

The primary object of this invention is to provide an improved method of producing bag-like commodity receptacles having therein several segregated material confining compartments, and improved apparatus for effectively performing the successive steps of the new method.

When merchandizing various commodities it is frequently desirable to be able to pack several independent batches of the same or different materials in the same package or confining receptacle, and it is also often desirable to be able to separate or divide the initial package into a number of smaller divisions each containing a lesser batch of the material. This type of merchandizing has been employed in various industries, but it is especially useful when applied to the confinement of bulk material in flexible bag-like containers formed of transparent heat-scalable sheet material. The prior methods and apparatus utilized in the production of such multiple compartment receptacles formed of flexible sheet stock have all been objectionable either because the resultant container did not effectively segregate the confined batches, or the receptacles were of insuflicient strength, or the methods of production were too slow and tedious, or the several divisions could not be readily separated, or the cost of manufacture was prohibitive.

It is therefore an important object of the present invention to provide an improved method of and apparatus for producing multiple compartment bags, which obviate all of the above-mentioned objections and results in the production of sturdy and effective commodity receptacles in rapid succession and at extremely low cost.

Another important object of this invention is to provide a. method of forming successive dual chambered bag-like receptacles from a longitudinally advancing ribbon of flexible heat-sealable stock, with the aid of simplified bag forming equipment.

A further important object of the invention is to provide a simple but eflicient method of manufacturing baglike containers for segregated batches of diverse commodities, in a manner whereby the containers may be readily divided into several sections each confining an independent batch of the commodity.

Still another important object of our invention is to provide improved automatically functioning apparatus for producing a succession of multiple compartment bags in accordance with the new method, by longitudinally advancing and inwardly folding the opposite sides of a heat-sealable flexible ribbon to provide overlapping edge portions extending throughout the ribbon length, by simultaneously heat sealing the overlapped edge portions to each other and to the adjacent underlying body of the ribbon to produce segregated internal commodity confining zones adjoining the heat seal, and by finally transversely heat sealing the folded and longitudinally seamed ribbon at spaced intervals and severing the same into sections of any desired length in advance of the 3,016,806 Patented Jan. 16, 1962 transverse seals to produce successive bags each open at one end.

These and other more specific objects of the invention will be apparent from the following detailed description.

A clear conception of the successive steps constituting the new method, and of the construction and operation of one type of apparatus for carrying on the method commercially, may be had by referring to the drawing accompanying and forming a part of this specification wherein like reference characters designate the same or similar parts in the several views.

FIG. 1 is a diagrammatic perspective view of typical equipment for automatically exploiting the present improved method of producing multiple compartment bags; and

FIG. 2 is an enlarged transverse section through one of the improved dual compartment bags, the section having been taken along the line 2-2 of FIG. 1.

While the invention has been described and illustrated herein as being especially applicable for the production of successive two compartment bags from a continuous longitudinally advancing ribbon of heat scalable flexible stock, it is not intended to restrict its use to such application; and it is also contemplated that specific descriptive terms employed herein be given the broadest possible interpretation consistent with the actual disclosure.

Generally defined, the present improved method of producing multiple compartment bags, comprises the steps of inwardly folding the opposite sides of a flexible sheet to provide overlapped edge portions spanning the sheet in one direction, sealingly securing the overlapped edge portions to each other and to the adjacent body of the sheet to produce adjoining but segregated tubular zones within the folded sheet, and finally closing the corresponding ends of the tubular zones transversely of the direction of extent of the overlapped edge portions to complete the several bag compartments.

In order to enable rapid production of successive completed bags, it is also preferable to form them of a longitudinally advancing ribbon of the sheet stock and to overlap the opposite sides of the ribbon and sealingly unite them so as to produce a seam extending in the direction of the ribbon advancement, and to thereafter periodically seal the ribbon transversely and sever it into successive lengths each constituting a final bag. And in order to permit each multiple compartment bag to be separated into several independent divisions, it is moreover desirable to provide a tear line extending medially along the longitudinal seam, and all of these steps constitute auxiliary features of the present improved method.

FIG. 1 of the accompanying drawing illustrates schematically one type of equipment for rapidly and effectively carrying on the several steps of the method to produce successive completed multiple compartment bags each having a transverse cross-section such as shown in FIG. 2. In the drawing, a flexible ribbon 5 of heatsealable stock is adapted to be constantly withdrawn from a stock supply roll 6 and caused to coact along its opposite sides with forming devices 7 to fold its longitudinally advancing edges 8, 9 inwardly into overlapping condition.

The folded ribbon 5 then advances between a set of cooperating and oppositely rotating lower and upper draw rolls 10, 11 having annular medial electrically energized heating elements 12, 13 adapted to coact respectively with the bottom of the advancing ribbon and with the upper edge 8 to heat seal the edge 8 to the underlying edge 9 and the latter to the underlying body of the ribbon 5 so as to produce a pair of tubular segregated interval zones 14, 15 adjoining the heat sealed seam 16 as illustrated in FIG. 2. The medial portion of the longitudinally advancing seam 16 is then subjected to a scoring or perforating rotor 17 which may be driven in any suitable manner to provide a weakened tear line 18 located mid-way between the side edges of the heat seal.

The folded, longitudinally seamed and perforated ribbon is thereafter passed between a second set of rolls 19, 20 ofwhich the lower roll 19 is provided with several rectilinear peripheral electrically energized heating elements 21 and with adjacent detents 22, while the upper roll20 is likewise provided with several rectilinear peripheral electrically energized heating elements 23 and with adjacent shearing blades 24. When the rolls 19, 20 are revolving in opposite directions at a selected speed, the blades 24 of the upper roll 20 are periodically cooperable with the detents 22 of the lower roll 19 to shear thesuccessive bags 25 from the ribbon 5, and the heating elements 21, 23 of the rolls 19, 20 are also cooperable with the sheared ends of the ribbon 5 to heat seal these ends transversely and to provide bottom closure seams 26 for the successive completed multiple compartment bags 25.

The flat bags 25 thus produced may be stacked or hung for compact storage, or the zones 14, 15 may be loaded by depositing batches of similar or different commodities into their open ends 27, whereupon these ends may be closed and sealed in any suitable manner to complete the successive packages. The purchasers of the final packages may open either one or both compartments at the same time, or may readily separate these compartments by utilizing the tear line 18 if the contents of only one compartment is to be dispensed, and if the compartments are thus separated the divided seam 16 will still effectively seal the adjacent sides of the separated zones 14, 15 since the tear line 18 is disposed midway between the opposite edges of the relatively wide heat sealed seam 16.

The length of the bags 25 may be accurately predetermined by varying the speed of rotation of the severing rolls 19, 20, and the capacity of the machine may also be varied by changing the speed of the rotation of the draw rolls 10, 11, while the heating elements 12, 13, 21, 23 may be energized in a well known manner electrically through wiring disposed axially of the various rolls. It is also noteworthy that more than one heat seal 16 extending longitudinally of the tubular ribbon 5 may be provided in order to produce a plurality of segregated zones, and that the overall width of the folded ribbon may be variedby adjusting the initial folding devices 7.

From the foregoing detailed description of the construction and operation of the multiple compartment bag making apparatus, it should be apparent that when properly installed and adjusted this equipment will function to rapidly and effectively produce the successive bags 25 in accordance with the improved method automatically and in rapid succession. The formation of the center heat sealed seam 16 of three ply thickness considerably reinforces the center of each bag and also provides durable seals for the adjacent side edges of each division when the compartments are separated along the tear line 18. The improved apparatus is exceedingly simple and is also capable of convenient adjustment to produce bags 25 of various sizes and shapes.

It should be understood that it is not desired to limit this invention to all of the specific method steps or to the precise construction of the apparatus described and shown herein, for various modifications within the scope of the appended claim may occur to persons skilled in the art.

We claim:

The method of producing successive unitary multiple compartment bags, which comprises, inwardly folding the opposite sides of a longitudinally advancing flexible ribbon to provide overlapped edges extending throughout the ribbon length, attaching the overlapped advancing ribbon edges to each other and to the adjacent ribbon body along a single longitudinal seam to provide a three-ply seal while dividing the ribbon into segregated tubular compartments extending throughout the ribbon length, longitudinally medially perforating the longitudinal seam to provide a tear line for effecting subsequent separation of the sealed compartments, and finally completing the successive multiple compartment bags bytransversely sealing the folded longitudinally seamed and perforated ribbon at spaced intervals and by severing the latter into bag lengths adjacent to but beyond each transverse seal.

References Cited in the file of this patent UNITED STATES PATENTS 2,347,439 Shea et a1. Apr. 25, 1944 2,423,187 Haugh July 1, 1947 2,565,444 Waters Aug. 21, 1951 FOREIGN PATENTS 435.943 Great Britain Oct. 2, 1935 

